An unusual mosaic structure of the PIM gene of Theileria parva and its relationship to allelic diversity

Geysen, Dirk; Bazarusanga, Thomas; Brandt, J.; Dolan, T.T.

doi:10.1016/j.molbiopara.2003.10.004

Cited by 23 publications

(18 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since MSA-1 is encoded by a single copy gene, it was somewhat surprising that the MSA-1 sequences varied so extensively, and that they varied in all but one breakthrough isolate. Similar, but less extensive variation has been seen in the single copy surface protein genes of other apicomplexan hemoparasites, including the merozoite surface proteins of Plasmodium falciparum (28), the major merozoitepiroplasm surface antigen (Tams1) of Theileria annulata, and the polymorphic immunodominant molecule (PIM) of Theileria parva (11,12). Genetic exchange is postulated to be the major means of generating polymorphism in these single copy genes, and in MSA-1, and most likely arises during diploid or polyploid stages in the respective vectors (11,12).…”

Section: Discussionmentioning

confidence: 78%

“…Similar, but less extensive variation has been seen in the single copy surface protein genes of other apicomplexan hemoparasites, including the merozoite surface proteins of Plasmodium falciparum (28), the major merozoitepiroplasm surface antigen (Tams1) of Theileria annulata, and the polymorphic immunodominant molecule (PIM) of Theileria parva (11,12). Genetic exchange is postulated to be the major means of generating polymorphism in these single copy genes, and in MSA-1, and most likely arises during diploid or polyploid stages in the respective vectors (11,12). No obvious sites of recombination could be identified among the MSA-1 sequences derived in this study, unlike the related MSA-2 genes in which a conserved site of recombination has been found (10).…”

Section: Discussionmentioning

confidence: 78%

See 1 more Smart Citation

Sequence Variation and Immunologic Cross-Reactivity among Babesia bovis Merozoite Surface Antigen 1 Proteins from Vaccine Strains and Vaccine Breakthrough Isolates

LeRoith

Brayton

Molloy³

et al. 2005

Infect Immun

View full text Add to dashboard Cite

The Babesia bovis merozoite surface antigen 1 (MSA-1) is an immunodominant membrane glycoprotein that is the target of invasion-blocking antibodies. While antigenic variation has been demonstrated in MSA-1 among strains from distinct geographical areas, the extent of sequence variation within a region where it is endemic and the effect of variation on immunologic cross-reactivity have not been assessed. In this study, sequencing of MSA-1 from two Australian B. bovis vaccine strains and 14 breakthrough isolates from vaccinated animals demonstrated low sequence identity in the extracellular region of the molecule, ranging from 19.8 to 46.7% between the T vaccine strain and eight T vaccine breakthrough isolates, and from 18.7 to 99% between the K vaccine strain and six K vaccine breakthrough isolates. Although MSA-1 amino acid sequence varied substantially among strains, overall predicted regions of hydrophilicity and hydrophobicity in the extracellular domain were conserved in all strains examined, suggesting a conserved functional role for MSA-1 despite sequence polymorphism. Importantly, the antigenic variation created by sequence differences resulted in a lack of immunologic cross-reactivity among outbreak strains using sera from animals infected with the B. bovis vaccine strains. Additionally, sera from cattle hyperinfected with the Mexico strain of B. bovis and shown to be clinically immune did not cross-react with MSA-1 from any other isolate tested. The results indicate that isolates of B. bovis capable of evading vaccine-induced immunity contain an msa-1 gene that is significantly different from the msa-1 of the vaccine strain, and that the difference can result in a complete lack of cross-reactivity between MSA-1 from vaccine and breakthrough strains in immunized animals.

show abstract

Section: Discussionmentioning

confidence: 78%

Section: Discussionmentioning

confidence: 78%

Sequence Variation and Immunologic Cross-Reactivity among Babesia bovis Merozoite Surface Antigen 1 Proteins from Vaccine Strains and Vaccine Breakthrough Isolates

LeRoith

Brayton

Molloy³

et al. 2005

Infect Immun

View full text Add to dashboard Cite

show abstract

“…For T. parva, the polymorphic immunodominant molecule (PIM) gene was amplified using a set of primers as described elsewhere (Geysen et al 2004). Moreover, the p104 gene was amplified according to Skilton et al 2002.…”

Section: Cloning and Sequencingmentioning

confidence: 99%

Epidemiological studies on tick-borne diseases of cattle in Central Equatoria State, Southern Sudan

Salih¹,

Hussein²,

Seitzer

et al. 2007

Parasitol Res

View full text Add to dashboard Cite

A herd-based study was carried out in Central Equatoria State, Southern Sudan, to study epidemiological aspects of tick-borne diseases. Six herds of cattle situated in three different locations were selected and investigated every 3 months during the year 2005. Blood smears for Giemsa staining and blood spots on filter paper for deoxyribonucleic acid extraction were collected from 600 apparently healthy indigenous cattle. A total of 69 (11.5%) samples showed the presence of piroplasms in Giemsa-stained blood smears, and polymerase chain reaction increased the detection limit to 297 (49.5%). Using reverse line blot, it was possible to detect and differentiate eight different piroplasms namely, Theileria parva (71.2%), Theileria mutans (73%), Theileria velifera (45.3%), Theileria taurotragi (2.7%), Theileria buffeli (0.5%), Theileria annulata (0.2%), Babesia bovis (1.7%), and Babesia bigemina (0.3%). Mixed infections were detected in 406 samples (67.7%) accounting for 17 different combinations. High infection of Theileria parva was reported among young calves compared to older cattle. The highest prevalence of Theileria parva was reported in the rainy season (October). The implications of these results on the epidemiology of tick-borne diseases are discussed with emphasis on East Coast fever.

show abstract

“…Cattle-tick-cattle transmission is thought to be limited as erythrocytic piroplasms are either absent or at an insufficient level to infect new ticks. The use of molecular characterisation tools has revealed a high level of diversity among buffalo-derived T. parva stocks compared to cattle-derived T. parva stocks (Bishop et al, 1994;Collins and Allsopp, 1999;Geysen et al, 2004;Oura et al, 2004a). Thus, there is growing evidence that only a limited subset of the total T. parva gene pool present within buffalo has become established in cattle.…”

Section: Introductionmentioning

confidence: 99%

Haemoparasite prevalence and Theileria parva strain diversity in Cape buffalo (Syncerus caffer) in Uganda

Oura

Tait

Asiimwe

et al. 2011

Veterinary Parasitology

View full text Add to dashboard Cite

An unusual mosaic structure of the PIM gene of Theileria parva and its relationship to allelic diversity

Cited by 23 publications

References 49 publications

Sequence Variation and Immunologic Cross-Reactivity among Babesia bovis Merozoite Surface Antigen 1 Proteins from Vaccine Strains and Vaccine Breakthrough Isolates

Sequence Variation and Immunologic Cross-Reactivity among Babesia bovis Merozoite Surface Antigen 1 Proteins from Vaccine Strains and Vaccine Breakthrough Isolates

Epidemiological studies on tick-borne diseases of cattle in Central Equatoria State, Southern Sudan

Haemoparasite prevalence and Theileria parva strain diversity in Cape buffalo (Syncerus caffer) in Uganda

Contact Info

Product

Resources

About